Injection apparatus for combustion engines, etc.



July 23, 1929. A. TACCHELLA 1,721,383

INJECTION APPARATUS FOR COMBUSTION ENGINES ETC Filed Jan. 26, 1921 ATTORNEYS Patented July 23, I929.

UNITED STATES .1 ,721,sss,

PATEN -caries.

ADOLF TAooHELLa, or sr. LoUIs, MIssoIIRI, AssIeNoa. T0 BUSCH-SULZER Janos.- DIESEL ENGINE CQMPANY, on ST. LOUIS, MISSOURI, A CORPORATION or MISSOURI.

-, INJECTION ArrARA'rUs FOR ooMBns'rIoN ENGINES, Ere.

Application filed. January 2 6, 1921. Serial No. 439,896.

My invention relates to fuel injection apparatus for engines of the so-called solid inj ection type and more especially to the spray nozzles thereof and consists in the use of certain nozzle structures hereinafter explained for maintaining predetermined characteristics of the spray under varying engine speeds and loads, thereby improving the economy, flexibility and commercial utility of this type of engine.

In engines of the 'kind referred to it is a matter of -much importance that the fuel I charge shall be injected with a proper velocity and in a state of suflicient fineness of atomization to combine effectively with the air charge and difliculty is experienced in designing the injector means so that these conditions shall be maintained under variation of the amount of fuel injected and under variation of the velocity of the pump plunger or whatever means is used for impelling the fuel as well as under variation of the compression of the air charge. It is, in fact, a recognized limitation of engines which inject their fuel, without the use of high pressure injecting air that their best efficiency is limited to only a narrow range of speed or load variation and the reason for this limitation is correctly assumed to be largely the effect of inadequatespraying when the speed or load has changed, Efi'orts have been made to correct the inadequate spraying by employing injection orifices normally closed by spring seated valves but these have not proved to respond with 'suflicient delicacy to changes in the amount of charge. I have, however, secured the requisite responsiveness and range of capacity by providing a nozzle having a normally closed, elastic and self-adjusting orifice, which, yielding to the varying pressure of the charge, provides an opening exactly appropriate to it and produces a spray blast emi: nently suited in respect to direction andfineness of atomization to a wide range of variation of engine conditions. Such an orifice has a tendency to maintain a constant or at least an adequate spray Velocity for all volumes of liquid discharged and varying injection pressures, respondlng instantly to the pressure of the charge. A

'Referring to the single sheet of drawings forming a part of thisapplication, Fig. 1 is an elevation partly in section showing one embodiment of my fuel injection apparatus in which a fuel measuring pump is employed, d rectly associated with each injector nozzle. Figure 2 is an enlarged detail view showing gerated view of the elastic lips flexed out-ward by the passing charge.-'

Figure 3 is a section online III-III look in in the direction of the arrows, and

igure 4 is an elevation partly. insection showing an embodiment of my invention in which the injection plunger serves also as a pump and is governor controlled.

In a wall of the combustion space preferably in the cylinder head 1, is mounted the injector nozzle 2, in the body of which is a cavity in which are located the plug the elastic orifice and in dotted lines an exag,

3 and a locking plug 4 which retains the other plug in place adjustably. Back of the lock ng plug is a fuel chamber 5. The self-ad- 6 normally in contact with the surface. 7 of the plug adjacent its end. The elastic seat is conveniently produced by two or more cross slots 8 in the metal ring surrounding the end of the plug. The ring is thus divided into two or more flexible elastic lips. The self adjusting orifice is adaptedto deliver a non-divergent and preferably a convergent spray. This is best accomphshed as-illustrated by'making the end of the plug conical and by employing flexible elastic lips and giving them aninner surface of the same form as that of the end of the plug. Con structing these contacting surfaces so-that theyjare' surfaces of revolution on theaxis of the plug having converging elements results' in a converging delivery of the spray from each orifice and from both the opposed right angles to its axis, so that they may be described as transverse annular grooves. Fuel supply grooves 10 arranged symmetrically are provided in the plug 3. and are fed by passages 11 in the locking plug 4, preferably diverging from points near-the axis of the plug toward its periphery and outerface;

The number of the supply grooves may be usting orifice is formed by the elastic seat 7 varied as may seem desirable and transverse collecting grooves 12, slightly less than semiannularito which passages ll-deliver may be provided in the locking plug 4, particularly where the plug 3 is providedwith several supply grooves or conducting passages. These details while preferred may be varied. An injection plunger 13 located inthe axis of the body ofthe nozzle is mounted for reciprocation therein and in the oil or liquid fuelchamber 5. The customary gland 14 is provided. This plunger is given reciprocation by lever 15 actuated by the usual fuel cam 16.

Different means for varying the amount of the charge may be employed. The injection plunger may itself act as a pump for supplying the fuel chamber with fuel, or a separate measuring pump may be used as indicated R diametrically at 17 in Figure 1, this being I the preferred arrangement. T his pump connected with the chamber by pipe 18, valve casing 19, in which is interposed check vali e 20, and passage 21 and drawing in fuel through pipe 22 may be controlled by the usual governor 23 so that the charge varies with the load. With this arrangement it is not necessary to provide means for varying the stroke of the injection plunger which is moved down the full length of its stroke at each revolution of the fuel cam and is moved the lever 15. In this form a spring 25 reaeting against plate 26 carried by the plunger.

and the gland bushing is provided to return the injection plunger. Of course other means for varying the charge may be used if desired.

It will be apparent that this invention increases the range of speed and load variation through which the best efficiency of the engine is secured, since it insures adequate spraying throughout such increased range,

' adequate spraying implying maintaining the 4 relative to the axis of said nozzle and contact- 7 ing over aconsiderable area and maintained in close contact subject to relative separation by temporary deformation of the elastic member by the fuel under pressure to. provide between them a self-adjusting, self-closing orifice sufficient .to allow the charge to pass.

2. A normally closed sprayingnozzle for combustion engines having a liquid fuel receiving chamber, a plug having contact surfaces adjacent its end, separate elastic lip segments normally in contact therewith and capable of being flexed independently, trans verse passages slightly less than semi-annular in extent in said plug, both located in said contacting surfaces and each opposite one of said lip segments and feeding fuel to it separately, and grooves for conducting liquid fuel to said semi-annular passages, the said lip segments being adapted tobe separated by pressure of the charge sufliciently to let it pass.

3. A fuel injection nozzle for solid injection engines having a metal body provided with a cavity extending lengthwise thereof and hav ing a hole in its delivery end of less cross sectional area than that of the cavity, the end wall of the body adjacent the hole providing elastic flexible members integral with the body and projecting therefrom longitudinally of the body and inward and having free ends, and a plug closing said hole and held in close contact with inner surfaces of said flexible members, the latter being subject to'flexure by the fuel under pressure to permit its injection between them and the plug.

4. A fuel injection nozzle for combustion engines having a plug having a conical end, and-a seat member normally held in close and extended contact with the conical surface of said end, said seat member having elastic conical segments having free ends and between which and the plug the injected fuel may force its way by momentary deformation of the segments.

5. A fuel injection nozzle for combustion engines having a plug with a conical end, and flexible lips having a conical inner surface with which opposite sides of the conical end of said plug are normally in contact subject to separation by fuel charges forced between them, diametrically opposite transverse liquid fuel grooves adjacent each pair of contacting surfaces, and symmetrically arranged passages for conducting liquid fuel to said transverse grooves.

6. A fuel injection nozzle for combustion engines having diametrically opposed sets of normally contacting surfaces providing elastic self-adjusting and self-closing delivery orifices ,opened by pressure of the passing fuel charge and located to deliver converging sprays of liquid fuel injected therethrough.

7. A fuel injection nozzle for combustion engines having a plug member. and a seat member having extended normally contactingsurfaces inclined at an acute angle to the axis of the nozzle, said seat member being of flexible elastic metal, the opposed surfaces of the plug and seat being adapted to be sepaplug having converging elements, said conrated by pressure of injected liquid suflicienttacting surfaces being adapted to be separated l0 ly to let; the liquid pass. by injected charges of fuel to let the same 8. An injection nozzle having a body propass. vided with a flexible elastic seat and a plug In testimony whereof, I have signed this normally in contact therewith, the contactspecification.

ing surfaces of said seat and plug being common surfaces of revolution on the axis of the ADOLF TACCHELLA. 

